JP-A-2000-203235 discloses a centrifugal blower unit for an inside and outside air double-layered flow type vehicular air conditioner. In the centrifugal blower unit, a divider is provided to restrict mixture of two kinds of air blown by a centrifugal fan.
The centrifugal fan generally sucks air in an axial direction and blows it in a radially outside direction. As shown in FIG. 5, air that flows above a divider 103 and enters between blades 101 partially blows downward under a divider 102, as denoted by an arrow, by its inertial force while changing its flow direction. As a result, air separability is lessened. Further, the air, which blows downwardly through the blades 101, is likely to strike against an end of the divider 102 and cause turbulent air flow, resulting in noise.